Sudden infant death syndrome (SIDS) is the unexplained death, usually during sleep, of a seemingly healthy baby. Sudden infant death syndrome is sometimes called crib death.

The exact cause is unknown, but sudden infant death syndrome may be associated with abnormalities in the portion of an infant's brain that controls breathing and arousal from sleep. Although all babies are vulnerable, certain sleep environments have been linked to increased risk.

Perhaps the most important way to reduce the risk of sudden infant death syndrome is to place your baby on his or her back to sleep, on a firm crib mattress covered by a fitted sheet. Nothing else should go in the crib with your baby — no blanket, pillow, bumper pads or toys.

Oct. 21, 2011